Downgading bootloader on 1.1.3 (devteam). Safe? Can I keep my stuff?

[TheDude42]

I have a 1.1.3 OTB phone that I activated, jailbroke, unlock using the non-ziphone method (downgrading to 1.1.1 working my way back up, installing dev team soft upgrade, etc).

I'm considering downgrading my bootloader with Ziphone so that a) my google locater will work, b) I can upgrade to 1.1.4, c) general easiness of hackery in the future.

Am I safe (relatively speaking) to perform this operation? Do I have to wipe/restore my iphone first? If not, will I retain all my info/pictures/apps/etc? What do I have to do afterwards to get up to the proper baseband?

(I should have put this in the downgrading etc forum...oops)